As health care technology increases in complexity and precision, survival rates among seriously ill and injured patients have increased. Frisk for pressure ulcers (PUs) is a significant nursing problem in this population. The total national cost of PU treatment has been estimated to exceed 1.335 billion dollars. Accurate nursing assessment, nursing diagnosis, and prompt nursing intervention are required for recognition and relief of pressure. In situations where pressure can be relieved, PUs can often be prevented. Current nursing risk assessment tools consist of subjective risk scales that have not been shown to be reliable across populations. My long-term research goal is to develop an objective measure of PU risk that is reliable and valid across populations. This experimental study will test the precision and accuracy of two promising noninvasive measures, transcutaneous oximetry and skin surface temperature, to identify PU risk in two contrasted groups of hospitalized adults: those who make gross or subtle movements and those who do not move. Pressure-induced, transitory circulatory impairment will be accomplished by placing the subject in the supine position in bed for 2 hours. Collected data will be entered into a computer and analyzed using SPSS for Windows (version 9.0)